All members are allowed to invite their friends to join and use the Discord server.

We encourage this.

We also encourage you to invite public members who regularly play on the BF or Insurgency servers to join too. It makes gaming more fun and encourages them to consider joining EBS if they haven't already. We only ask that they're sensible and obey the same gentlemanly manner we expect from each other.

To invite, right click a channel, select "create instant invite" then copy the link and send to your pal. EASY.

Also, how to we invite him to discord? Do we need an admin to do that?
I think anyone can send an invite. Just right click a channel and click "instant invite". Then copy, paste and send the link via Steam or whatever